Proportional-flow device



Jan. 5 Q1926. 1,568,619

E. B. PHELPS PROPORTIONAL FLOW DEVICE Filed August 7, 1922. 2Sheets-Sheet l Ev e-sad 07175 I Jan 1926. 1,568,619

E. B. PHELPS PROPORTIONAL FLOW DEVICE Filed August 7.v 1922 2Sheets-Sheet 2 attmvlaqi To all who mit mag concern:

. new "and useful Improvements in Propor-' Patented Jan. 5,.1 926 VUNITED-STATES EARLE IBERN ARD PHELPS, OF RIDGEWdOIl, NEW J'ERSEY.

' rnoronrronaL-rrow Davida.

7 Application 111m August 7," 1922f seiia1m. 580,280;

K tional-F low :D'evic'es, of which the following is a specification; vp I Th s invention relates tohydrauhc measuring .devices andparticularly to automatic means for producing proportional 'flow of twostreams of liquid, subjectto independent changes of head and havingeitherthe, same ordiflierent specific gr a-vities.v

Devices of this character are 'u'sefulin a number of industrialoperations whereit is desirable to add a small stream of somechemicalsolution to a larger stream of some liquid, maintaining a,constant rate or proportion, As an example offsuch operations I maymention the process. of purifying water by adding a 'solution ofsulphate'of alumina. i

a The invention offers a simple means of automatic control actuatedsolely by hydraulic head, and, in the preferred form susceptibleofadjustment to vary the proportional rate. Stated in its simplestterrnsthe invention involves the use of two measuring devices'having'.the same flow law or formula,

for example two fixed orifices, orv two. weirs of the sametype, and theautomatic control of the head on one measuring device by thevarying'head on the other. i

In the drawings:- r 'Fig. 1 shows a simple embodiment of the inventiveprinciple involving the use of fixed orificesp" p v Fig. 2 "illustratesthe substitution of V-notchfweir's for the orifices usedin the structureof Fig.1;and I U i I Fig. 3 shows a refinement of the structure of Fig.1, having certain features. adapting it for commercial use.

Referring first to Fig l, the source of the mainor controlling stream,"whose flow rate 'maybe widely variable, is indicated by the pipe 6'. Thepipe GdiScharges into a tank 7 havingthefixed orifice 8 in its bottom."The tank 7 hasawell 9f'i'n its bottom to" permit a bell 10 to besubmerged in'the'tank with itsflower margin, at the level of thedefining edge'of orifice 8. I I f f Thesou'rce of the controlled stream?is the tank 11, which communicates throu'gh-a. pipe 1 "12 and'regulative valve 13, controlled by a ball float 14, with closed pressurecontrolling. chamber 15. The chamber :15 commun1cates through a pipe 16,with'a variable head tank 17 and in the bottom of tank 17 is afixed-orifice 18 similarin form to but' usually smaller in size than theorifice 8;

The tank 17 is shown open to the atmosphere and in such case the totalhead on orifice 18 is the static head'due to the height of the liquid inthe tank. If the tank '17 were closedat its'top with a'confined body 7of air above the liquid, the total head on orifice 18 would be thestatic head due to the height of the liquid plus the'pressure head dueto the compression-of the confined air.

As is well knownthe'totajl head is the sam in these two cases.

- In order that" the total head on jorificell8 v shall be kept equal, orapproximatelyequal, to the head onorificefS the ball float 14 worksbeneath a dome 19, on top ofgchamber v, p

15, connected b an air-filled pipe; 20"with the bell 10, an

relatively to valve 13 as-to open the valve whenever the liquid levelunder the dome falls below the level of the defining edge of orifice 18.

Hence the total heads on the orifices Sand 18' are balanced one againstthe other by the air pressure communicated by pipe '20 between bell 10and dome 19. v 4 To avoid errors incident to the entrance of liquid intobell 10 under increases-of head in tank 7 and also those necessarilyoccasioned by changes of; temperature and 'air' leakage, it ispractically*desirable' to feed air to the air line. ThisI do through apipe 21 connected t'opipe 20. The air is constantly supplied at aslowrate under: a pressure slightly *greater than that corre-Consequently the heads on the orificesj8 and 18 are "maintained equal at"all'time's. Since the rate of. flow through. an orifice varies thesquareroot of the head, the flows through the two orificesjvary at equalrat'es,-- maintaining [a c'onst ant' proportion which is fixed bychoosing the relative sizes oforifices8 and'18.

from that of Fig. 1 onl in'thefsubstitution of V-no'tch, wiers 8 an 18for the orifices 8 and 18, respectively. Otherarts are identical withthose illustrated .111 Fig; ,1

the float let is so adjusted In Fig. ears. illustrated a device.difiering and art? serially nirmbr d, should be note'd'that' the bottomor apex of the wennotch 8 is level With the margin of bell l0 and theapex of notch 18 is" at the level.

maintained under dome 19 by float 14 and valve 13.

In the case of V-notch weirs the rate of In Elg. 3 I show a device inwhlch I elmnnate the:regulativevalve 13. The function of this valvev inFig. 1 is tova'ry the quantity. of liquid supplied to the variable headtank 17 so as to maintain in this tank a static head equal'to thepressure head exerted by the air. ln the structure of Fig. 3 there is novariable head tank and the pressure head exerted, by the air directlydetermines .the rate of outfi'ow through the controlled orifice. Theexcess above such outflow, discharges through an overflow and maybedisposed of as desired. Usually it would be pumped back to the source hA The device of Fig. 3 is fundamentallv igdenticalwith that of Fig.1 andthe functionally identical parts inthe two structures areidentifiedby,the same reference numeral. LTllQ PlPQ 6 is the supply ofthe main or controlling liquid, and discharges into a tank 7 havingafixed orifice 8 in its bottom. Thebel'l 10; here shown as an elbow con.-nection w its end turned down, is mounted {tshortdistance above thedefining edge of they orifice 8, The purpose of so mountsth l er llhemad P a n h e t r-i The s ource, of the controlled liquid flow is thetank 11 elevated to give a-static head sufficient; to produceflowthrough the pipe 12 at least equal to, and preferably slightlyxceeding the maximum outflow through the control-le d orifice1 8. Thepipe 12 leads it -the p i hrh he hel-hh h r and t e ifi9el is in the botom, o t m e between the point of discharge of pipe 12 barrier ordain 22whose purpose is t m i ain? pq h f iq id above t fice 18 whose depththree or more times th names the eerifi -.v Th pu p e of this is toinsure sufficient, submergence of the orifi ce 1 8. to stabilize; thecoeflicient of dishh r eh been f df 2. made equal, or s ibstantiallyequal to the distance that; the hell IQ is spaced above the definingedge ofthe orifice 8.. The bell 1O throughthe pipe 12 at a rate fasterthan the possible outflow through orifice 18 maintariffs pool ,of'liquiid of aipp'fokimately ;onstafft depth over the orifice '18; Suchliquid as does not flow out through this ori- ,fice escapes .overzthedam and into a trap or manometer U tube consisting of the verticalbranches 23 and 24 connected at their lower ends.

rte Branch llas an overflow 25 at its upper end arranged at, orpreferably slightly below, the crest of the darn 22., he l'iq'uidoverflowing from the over-Haw 25 may be run to waste or may be pu'n'ipedback to tank 11 heretofore suggested. I q The air pressufe existirig intlle pipe 20 is' 'liinited ,to avalue corresponding to the static headat the lower edge; or ten 10], the air escaping around the lower edge ofthe bellat stich rate as is necessary to limit the pres-sine t6 thisvalue. Qonseqnefitly the chamber 15' is subjected to ate: same pressiireand the liquid column in the branch 23 is depressed below the level ofoverflow 25a distance equal to the submer enee (if the belllO' Theeffective head on theofifice 18 its the static head corresponding to theheight of the dam 22 plust hei pressure head 'ezterted by the air.Theleli' ective head on the orifice}; is the same, being equal to thesane re ac ing t the meets or the bell 10 plus the static head due tothe vertical height of the orifice 8 below the bell If), this Verticalheight being'a's heretofore stated equal torts hei iht'of the am 22.

gn willbe' odserired, therefore, that the spacing tithe bell 10 abovethe orifice 8 is for thepurpose of compensating for th lcoristant statichea'd naintained onthe orifice 18 by the dam 22, Tlie device will thusoperate to prodn ce" the desired pra drfiibnal flow througlrtheoi'ifi'ces 85nd 10 it ti effective heads equal to or greater than theheight of the dam 22.

The entire freedoni of the" device from 7' constrifctidn shown in 1 andj2 emhody i 5. 1 l m ina o of hi iiqhid-fl measuring orifices whoseflojvrates are similar functions of the respective effectivehydraulic'heads on said orifices; independent sonrces liquid for the two orifices,said sourcesbeing characterizedby variations of hydraulic head; a closedregulative chamber associated with the ,second orifice and partly filledwith'liquid fldivijiig to said second orifice; eans rat eziei tingpneumaticpressureon thel surface o f said liquid. increase the effectivelieadon the second orifice; and controlling means for draulic heads onsaidorifices; independent sources of liquid for the two orifices, saidsources being characterlzed by independent variations of hydraulic head;a closed regulative chamber associated with the second orifices andpartly filled with liquid flowing to said second orifice; a bell havingits bottom open and submerged in liquid flowing to said first orifice; apneumatic pressure transmitting connection between said bell and thespaceabove the liquid in said chamber; and means for feeding pneumaticpressure fluid to said connection at a pressure higher than thehydrostatic pressure on said bell.

3. The combination of two liquid-flow measuring passages whose flowrates are similar functions of the respective effective hydraulic headson said passages; independent sources of liquid for the two passages,

said sources being characterized by independent variations of hydraulichead, the

head on the second source being always the greater; a valve controllingand urged closed by the hydrostatic head on the second measuringpassage; a pneumatic pressure device urging said valve in an openingdirection; and means for limiting the pneumatic pressure in said deviceby the hydrostatic pressure on the first passage.

4. The combination of two liquid-flow measuring passages whose flowrates are similar functions of the respective efi'ective hydraulic headson said passages; independent sources of liquid for the two passages; avalve subject to and urged closed by the effective hydrostatic head onthe second measuring passages; a bell having its bottom open andsubmerged at the level of zero head on the first passage; and apneumatic pressure transmitting connection between said bell and saidvalve, whereby the pressure in the bell urges said valve in an openingdirection. w

5. The. combination of two liquid-flow measuring passages whose flowrates are similar functions of the respective effective hydraulic headson said passages; independ ent sources of liquid for the two passages;

a valve subject to and urged closed by the effective hydrostatic head onthe second measuring passage ;'a bell having its bottom open andsubmerged at the level of zero head on the firstpassage; a pneumaticpressure transmitting connection between said bell and said valve,whereby the pressure in the bell urges said valve in an openingdirection;

and means for feeding pneumatic pressure fluid to said connection at apressure higher than the hydrostatic pressure on said first passage.

In testnnony whereof I have signed my name to this specification.

EARLE BERNARD PHELPS.

